That's good news for some 50 million Americans who rely on the state-federal program for health insurance.

Like many federal agencies, the CMS (Centers for Medicare & Medicaid Services) hasn't issued a detailed public outline of its plans for a possible government shutdown, which could occur Friday at midnight if House and Senate leaders can't reach a budget deal.

But public officials in Washington and across the United States are generally expecting Medicaid's core functions to continue unimpeded, as long as any shutdown is fairly short. Some members of Congress have sought to reassure Americans with public statements.

"According to the House Committee on Energy and Commerce, because Medicaid allotments are paid to states in advance on a quarterly basis, it is likely states will not see an immediate impact from a temporary government shutdown," Rep. James Renacci (R) of Ohio says in a shutdown bulletin on his website. That means physicians and other health-care providers should continue to be paid as usual as they serve the Medicaid and SCHIP (State Children's Health Insurance Program) populations.

If Congress runs up to the midnight deadline with no plan to fund the government, federal agencies including CMS must designate which workers are performing essential work. Those people would be asked to stay on the job, while nonessential workers would be furloughed.

It's unclear if furloughs might have ripple effects for some Medicaid services, such as enrolling new beneficiaries for coverage.

Medicaid programs are administered at the state level with funds from both federal and state government.

Launched as a program for poor Americans, Medicaid increasingly acts as a safety net for older Americans who need long-term care arrangements. Medicaid is used by 42 percent of Americans in poverty, 21 percent of low-income adults, 56 percent of low-income children, and 70 percent of nursing-home residents, according to numbers tracked by the Kaiser Family Foundation.